Building a 3d projection system

[-bart-]

Hi all,

I would like to experiment with projecting some fullcolor 3d laser imagery on a wall/screen.
I plan to use two small projectors with rgb single mode diodes in them, placed orthogonal.
I'd rather not modify them with quarter waveplates if reasonable effects can be achieved leaving them H-V polarized.

I would like the result to be visible with (low-cost) ready available polarized 3d-glasses.
These all are afaik circular polarized glasses.
Do these glasses work with orthogonal H-V polarized images ?

Does anyone have experience with 3d laser projection setups, and would like to share some experience ?

[masterpj]

Hi all,

I would like to experiment with projecting some fullcolor 3d laser imagery on a wall/screen.
I plan to use two small projectors with rgb single mode diodes in them, placed orthogonal.
I'd rather not modify them with quarter waveplates if reasonable effects can be achieved leaving them H-V polarized.

I would like the result to be visible with (low-cost) ready available polarized 3d-glasses.
These all are afaik circular polarized glasses.
Do these glasses work with orthogonal H-V polarized images ?

Does anyone have experience with 3d laser projection setups, and would like to share some experience ?

I have experience with this.
Normally light needs to be projected on a silver screen though to maintain the polorization so even with a laser I have my doubts you can do the polorized 3D without projecting on a silver screen.
*proper polorization is lost as soon as it reflects hence the use of silver screens.

So far with LD2000 there are 3 options to my recollection of achieving stereoscopy:
- Anaglyph
- LCD Shutter glasses
- Trimagic (which seems to be a special laser projector) (Tim Walsh might be able to tell you more about this seeing he used one)

Edit: Just checked: Trimagic is an solution for getting the LCD shutter glasses technique to work...

"The Trimagic projector, manufactured by LaserAnimation Solligner of Berlin, Germany, uses a single pair or scanners and an “alternating frame” method of projection. The scanner projects one frame for the right eye, and then the next frame for the left eye. When viewers wear special stereoscopic glasses, they see a virtual 3D object that the brain creates from the two 2D views. "

I recommend you to go anaglyph.
If you really want to go polorized then you need a silver screen. I can help you further but it will require you to build 2 laser projectors both with opposite polorization.

*I recommend going for circular polorization method as in that doesn't require the head to be level.

Content making is tough but it can be done by creating a 3D enviroment and placing 2 3D cameras in 3ds max.
You render out both individual basicly meaning you have left and right in a seperate file.

Both projectors then need to play their own file at the exact same timing.

[Galvonaut]

Considered some polarised 3D laser ideas myself, so watching thread

Keith

[mixedgas]

There is a forth.method. The QM2000 provides a Z signal. With some external electronics this gives you a way to use two scan heads.

You get a X and X Prime signal after analog external processing.

Steve

[LaserWizard]

I do have a Trimagic projector from LaserAnimation, it works great when it is properly set up and controlled with the Lasergraph DSP. Except that it adds another layer of flicker to the images, and complex images do not work well. So I have no plans to use it except for programming; it is perfect for programming. You really need to see the depth when you are programming, and using one pair of scanners is the way to go to get instant feedback.

I am working on separate left eye/right eye orthogonally polarized projectors now, and I have it done except for the output scanners.... I need scanners with simple aluminum coatings to preserve the polarity, and most scanners now come with dielectric coatings that seem to seriously affect the polarity. I'm waiting for One Stop to send me a sample of Cambridge scanner mirror that is simple aluminum. Anyone know of any other source for plain aluminum coated scanner mirrors that will not change the polarity of the light that passes thru?

Tim

[LaserWizard]

More comments - Anaglyph is fine for 3D but it wears your eyes out quickly!

Crosstalk between the eyes is always a problem with polarized 3d and lasers, the light is so concentrated.

Then there are the guys in Fort Worth who do the school laser shows (Prismatic Magic, they came by TEXLEM in 2012), they have applied for a patent on a stereoscopic laser projection system using slightly different wavelengths for each eye. For example, use 640 red for left eye, and 670 red for right eye. Then have special glasses made to sharply filter each eye so that it gets the proper image. Expensive glasses to be sure, but you can project on any surface! I'm looking forward to seeing one of these shows someday.

[dsli_jon]

..Anyone know of any other source for plain aluminum coated scanner mirrors...

..Check with Bill Benner? 'betcha a sarsaparilla he knows-one...

cheers..
j

[planters]

Anyone know of any other source for plain aluminum coated scanner mirrors that will not change the polarity of the light that passes thru?

I know Nutfield Scanner company sources their various scanner mirrors from:

http://rmico.com/

They use protected silver and this should also be immune to depolarization. Because we almost universally send combined V and H (PBS combined) light through a scanner and the average reflectivity is very high I had assumed that the multi-stack dielectric mirrors did not alter or mix the polarization. That's interesting.